Die assembly



July 25, 1960 s. HOUVENER 2,946,090

DIEAssEMBLY Filed June 4, 195s INVENTOR. /rw'ny .5. Hoc/vener HGENT2,946,090 Y DIE ASSEMBLY ruled June 4, 1959, ser. No. 818,038 Achims.(c1. 1s-1z) This invention relates to extrusion dies and particularly toa `die assembly which includes means for inuencing the flow ofextrudable material through particular parts of the die.

Most extruded products are produced by forcing the extrudable materialdirectly through the opening of a die. The extrudable material, however,does not always ow at equal rates through all parts of die openings,especiall'y in those dies having non-uniform cross sectionalconfigurations. A considerable degree of skill has heretofore beenrequired to make a die having a configuration such that the productextruded therethrough is of desired cross sectional coniiguration, do'esnot warp due to uneven ow rate through the die, etc.

It is an object of this invention to provide an improved die assemblyfo'r extruding sections of irregular crosssectional configuration.

Ano'ther object of this invention is to provide an im` proved and moreeconomical extrusion die assembly.

A further object of this invention is to provide a die assembly whosei'low characteristics may be quickly altered to suit changes incharacteristics of the product being extruded.

In accordance with this invention there is provided a die assemblyincluding a die orifice, a mixing chamber disposed contiguous to andcommunicating with the o'ritice, means for introducing extrudablematerial to said mixing chamber, and adjustable means extending into themixing chamber for adjusting the flow of material through the dieorifice.V

The invention, as well as additional objects and advantages thereof,will best be understood when the following detailed description is readin connection with the accompanying drawings, in which:

Fig. l is an isometric view of two mating die assembly sections, shownin un-assembled fo'rm;

Fig. 2 is a sectional view taken along the line 2--2 of Fig. l;

Fig. 3 is a sectional view taken along the line 3-3 of Fig. l;

Fig. 4 is a fragmentary view looking into the exit face of an assembleddie assembly made in accordance with this invention; and

Fig. 5 is a fragmentary plan view of the face of the die'sectio'n whichabuts against the extruder.

Referring to Figs. 1, 2 and 3, there is shown a die assembly, indicatedgenerally by the numeral 10, comprising a die section, indicatedgenerally by the numeral 12, and a mixing and iiow control section,indicated generally by the numeral 14.

The die section 12 comprises a plate 15 having an exit face 116 and anentrance lface 18, the faces 16 and 18 being parallel. Four bores 20extend through the section 12 and are, for convenience as well aspracticality, disposed symmetrically around a die opening 22 whichlikewise extends through the section 12.

v The side walls 24 of the die opening Z2 are disposed perpendicularlywith respect to the section faces 16, 18.

`United States. Patcnt0- ,l 2,946,090 PatentedJuly 26,719.60I

ICC

with the lugs 30, 32 of the section 14, also extendV through the section12.V

The mixing and ilow control section 14 has a pair of iiat, parallelfaces, the exit face 34 being adapted to seat against the entry face 18of the die section 12. An array of four bores 35, corresponding in sizeand location to' the bores 20, extend through the section 14.

A counter bore 36 extends inwardly from the exit 34 face of the section14. The counterbore 36 is of larger diameter than the maximum linealdimension across the die opening 22 and is so disposed in the section 14that when the sections 12, 14 areassembled the counter boro surroundsthe die opening the section 12.

The depth of the counter bore 36 (which constitutes a distributio'nchamber) is a function of the dimensions needed to provide a mixingchamber having a desired volume inventory of the particular materialbeing extruded. Referring especially to Fig. 5, it may be seen that a.plurality of small bores 40 extend through the entry face 38 of thesection 114 and communicate with the counter bore or distributionchamber 36. As illustrated, 'the bores 40 are Adisposed adjacent to theperimeter of the chamber 36. The desired shape and cross sectional areaof the product to be extruded inuences the specific position of thedistribution bores 40 and the number of them depends on theconfiguration and total cross sectional area of the die opening.

It has been found that excellent extrudes are obtained when the combinedcross sectional area of the distribution bores 40 is approximately 80percent of the cross needed to' control the ilow of material beingextruded through the die orifice.

As mentioned before, the distribution chamber 36 is necessarily madelarger in diameter than the die opening 22 so that the distributionbores 40 need not be disposed in direct alignment with any part of thedie opening 22. By not having the distribution` bores 40 dischargingdirectly into the die opening 22, the ow of material which is to beextruded may be more evenly dispersed in the die opening 22 as a resultof the changing iiow pattern.

In operation, if the material being extruded flows more freely throughone section of the die opening than through another section thereof, oneor more iow control pins 42 is advanced into the distribution chamber 36in alignment with the part or parts o'f the die opening 22 where thenon-uniform iiowing occurs. If needed, the flow control pins or elementsmay be advanced into the die opening 22 itself rather than merely intothe distribution chamber 36 adjacent to the die opening.

Thus, while controlling the shape of the distributionV chamber 36 andthe number and positioning of the materials distribution bores 40 helpsto assure a somewhat uniform material iiow throughthe die opening 22,the adjustable llow control pins y42 provide more complete ilow controlmeans which can easily be adjusted to varyonthe entry face side 18 of(not shown) provide the means for locking the die as-i sembly to' anextruder or press.

What is claimed is:

1. A multiple part die assembly comprising a first plate and a secondplate, each of said plates having an entry face and an exit face, theentry face of the first plate being adapted to bear against the exitface of the second plate, said plates having means for indexingthemselves with respect to one another and for locking the platestogether, said rst plate having a die orifice extending between itsentry and exit faces, said second plate having a mixing chamber whichsurro'unds said die oriiice when the plates are indexed and bearingagainst one another, the mixing chamber extending inwardly from the exitface of the second plate, a plurality of feed bores, said feed boresextending from the entry face of the second plate into the mixingchamber, an array o'f bores, said bores extending from the entry face ofthe `second plate into the mixing chamber and being aligned with saiddie orifice of the irst plate when said iirst and second plate areindexed with respect to one an- Ahave shanks which are press tit intosaid array of bores.

4. A die assembly in accordance with claim 1, wherein at least one ofsaid o'w control elements extends into said die orifice when Vthe platesare locked together.

References Cited in the file of this patent UNITED sTATEs PATENTS1,228,495 Tanzi rune s, 1917 FOREIGN PATENTS 1,117,397 France Feb. 20,1956

